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I'm stuck with a lot of pale yellow emulsion which is refusing to separate back into the nice brown bromosafrole layer. Anybody have any ideas how I can fix this?

I have heard that running an emulsion through a filter can help, but I don't really understand why.

Possibly freezing the water would force the other solvents together and  out of the ice. or get it warmer so the bubbles of solvent join together more easily.

However no need to add more variables to the experiment so I guess just let it sit.
And also excellent posts!

The only time I've ever heard of using a filter to work with an emulsion is when using those watson phase separation filters.  Which are awesome and cheap.

It seems like it might be easier to take the Methylamine hcl that is in dry IPA already and just add enough NaOH to neutralize it.  We could run it under reflux to keep the gas from escaping and add the NaOH slowing with chilling.    Was wondering what ph does the IPA/Methylamine need to be?

don't waste your  time it does'nt work.
i tried that already
pm me and tell me what you are doing and i can probably staighten you out on that.
next time if the fumes get to you use full eye protection and a wet rag to breath through at the very least.
a fume hood would be prefferable but this is the real world.

Who thinks that changing solvent to something else than DCM would solve problem
of emulsions!?

DCM+bicarb=allmost allways nasty emulsion

Re DCM - He didn't need a solvent at all.

Re NAoh to IPA/MeAm solution:  You could silica or mol sieve to dry it.  Jon did you try that?  What was the problem?  It seems dumb to have methylamine in bone dry IPA and then add water during the gassing.

I appreciate the offer to help Jon, but since I'm not the one doing it and he has his own methods, I can't really say what he's doing wrong although I suspect that it's because he keeps trying to dry the gas (running it through a tube of mol sieve), so he's not getting enough throughput.  He's working microscale experiments.  

When you deal with someone who is Aspergers you learn that they have their own way of doing things and it's best not to try to hurry them.  I've had time to see how he works, once he gets something down, it is like a machine as far as reproducibility goes, plus he gets an understanding of things that is beyond what is published.  

When I did the ammonia gassing, I hung wet towels soaked in borax all around the area and had no problem with fumes except for the nasty dose I got when I tried mixing the ammonia with the base in a mortar.  Whew one whiff of that was enough for me.  

I mentioned the issue with my lungs cause I don't want the newbs to get the impression there aren't hazards involved.  We had test batches of Methylamine in progress most of the year so it's been a cumulative effect, mostly from when he's cleaning the glassware.

I think Jon takes good workup skills for granted not realizing some of us have never worked in a laboratory or had a chemistry class.  I spent a year learning how to do acid/base and distillations etc, but it still takes me a lot of time to do things and I make lots of mistakes.  

I didn't just read Jon's writeup's before I tried this.  (I read his writeups on 3 different forums as well as the ones while he was developing his method)  I went back and read some of the original journal articles as well as researched each chemical involved so I would have an understanding of what I'm working with.  

I've been researching microwave chemistry and am looking at some options to create the iodo directly.  I've attached some articles I've found on direct halogenation, I haven't yet determined if they are worth trying on safrole.  

Salat

@salat
The first two references you posted are inapplicable as they deal with iodination of arenes, not alkenes.

I don't see why you don't just drip supersat NaOH onto MeNH2.HCl.  If you decide to use mol sieves, make sure you use 3a

fuck running drying traps (did'nt i say they would clog and you would get back gassed?)
just bubble the shit in using a gas disperer at the end of the line and a suck back trap.
a little water gets in it's fine it will still work.
you are too anal about this.
drop the conc. naoh on to the methylamine slowly and cool down the gas generator so it does'nt steam water (it does'nt get hot if you use that order of addition of reagents anyway).
just keep it simple.

and mgso4 and cacl2 will complex amines i tried that too it did'nt work.

I have been working away on trying the seperate the emulsion and I think I have most of the bromosafrole separated now. The problem is that I still have a quite large organic layer left in the sep funnel which is a light cream colour. Is this possible just the a dilute solution of Bromosafrole in DCM. I really can't tell. I tried evaporating off some of the solvent under vacuum from a portion of the bottom yellow layer and it appears to get darker, signifying a concentration of bromosafrole in that layer?

Am I just taken shit? I'm not too sure!

Also I don't think I messed up the stoicometry? I have attached my calculations below. Let me know if you see a problem? Jon FYI I actually did show my calculations to you before I started!

-------------------------------------

This bromination employs 40% of HBr in Glacial Acetic Acid. The reaction to form the HBr procceds as follows:

H2SO4 + NaBr = NaHSo4 + HBr


Here is my calculated ammounts of reagents:
100ml Glacial Acetic Acid

Jon says to creare 40% solution of HBr in GAA (w/w?) therefore 40grams HBr in 60grams acetic acid

I want to use a scale of 100ml GAA. So 60grams is scaled to 100ml which is 105grams GAA
and the required ammount of HBr would be 70grams
70 grams HBr is 0.86 moles therefore 0.86 moles of NaBr is need to generate the the Hbr
0.86 moles of NaBr is 88.4 grams

To form the HBr you would teoretically need 0.86 moles of H2SO4 which is 84.4 grams.
Its best to less than needed H2SO4, 5% less would be 80.1 grams H2SO4 / 43.5ml

Jon says to use 1.9 mole HBr / 1mole Alkene.
We should have 0.86 moles of HBr therefore we should use 0.45 moles of safrole or 73grams/ 66.6ml
Or if using 80% sassafras in your calculations you would use 0.36 moles or 58.4 grams / 53.28ml

100ml / 105 grams GAA
88.4 grams NaBR
80.1 grams H2SO4
73 grams Safrole

P.S About the images below, I know that 3 destinct layers can't form. I would love if somebody could give me an idea of where I'm messing up! Thanks again for your help everyone!

Salat,you can't do ratios solely by weigh if someone gives you molar ratio,it's pointless!
Maybe you are trying to say something else ?

Patience is crucial here!
Take the brownish part,seal it in glass container and put in fridge,
let that leftower s..t to separate and repeat the process.

Halogensafrole tends to change color wildly depending on concetraction,sovent...
Keep that in mind!

Make sure to test it for pH before storing.
It shuld be neutral or close to neutral.

You mean you use less concetrated solution of Na2CO3 istead of NaHCO3?!